Grinding wheel truing apparatus



Aug. 22, 1939.

c. G.. FL-YGARE GRINDING WHEEL TRUING APPARATUS Filed Feb. 19, 1938 G. FLYGAPE Patented Aug. 22, 1939 2,110,605 Gal'NDrNG WHEEL 'riruma APPARATUS l Carl G. Flyrare, Worcester, Mass., assignoi to Norton Company, Worcester, Mass., a corporation ot Massachusetts ponemos February 1s, 193s, serial No. 191,497

8 Claims.

This Yinvention-relates to grinding machines, and more particularly to a grinding wheel truing apparatus for producing either a formed wheel,

or producing a radius'thereon, or a combination 6 radius and iormed face.

One object of the invention is to provide a simple and thoroughly practical combined form and radial truing device for truing theoperative lace of a' grindingwheel. Another object oi' the invention is Ito provide a truing devicein which either an irregular formed face maybe produced on the periphery vof the wheel or a curved face of a deiiniteradius. orifvdesired a combination of anirregular formed face together with a radial roce.v other objects wm be in part obvious or in part pointed out hereinafter.

i The invention accordingly consists in the features of. construction, combinations of elements, and arrangements of parts, as will be exempli'iled in the structure to be hereinafter described, and

the scope of the application o f which will be indicated in the following claims.

In the accompanying drawing in which is, shown one-'of many possible embodimentsof the mechanical features oi this invention,

Fig. l` is a fragmentary cross-sectional view through a portion of a cylindrical grinding machine, showing the improved truing apparatus in end elevation;

Fig.' 5 is ai'ragmentarydetail view 'oi'the parts shown in Fig. 3, showing the truing tool at thev opposite endcf itsy traversing stroke:

Fig. 6 is a fragmentary detail view, showing the manner in which the parts are arranged for ad justing the truingtool for-truing apredetermined radius on the wheelperiphery'; and v Figq 7 shows ,a horizontal sectional view through a work holding chuckv and headstock *1 spindle.

drawing comprising abase Il which-supports a longitudinally traversable work table I I on a V-'way I2 and ilatway I3.v 'I'he table II is provided with a depending rack bar. Il which meshes with a rotatable gear I6. gear II is mounted on the outer en d of a sh'i Il which is Joulllalled (cl. 12s-11) Fig. 2 is a rear elevation ci' the truing appa.-`

l A grinding machine has been illustrated in the in a suitable bearing within the housing I] which projects-from the front of the vmachine base I0. A manually operable hand wheel I8 is mounted on the outer end of the shaft I6 and 'serves to facilitate a manual traversing of the table Il, i5.; either for a grinding operation orto traverse a truing tool across the periphery of the grinding Wheel.

A rotatable grinding wheel I9 is mounted on al spindle (not shown) which ln turn is supported 10 on a. transversely movable wheel slide (not shown) which is fed transversely by means of a nutand screw feeding mechanism which may be actuated either automatically at. either end oi.' the table stroke or manually by means of a man- 1.5. ually operable hand Wheel (not shown). These elements are not considered to be a part of the present invention and consequently have not been illustrated in detail. These well known grinding machine elements are clearly illustrated 20 and described in the prior United States patent to Norton No. 762,838 dated June 14, 1904. i

A swivel table 20 of the well known type, such f 4as used in common practice on cylindrical vmachines, is mounted on top of the table II and is 25 pivotally adjustable thereon to facilitate setting up the machine so that the work axis is -parallel to or at an angle relative to the axis of rotation of the grinding wheel spindle.

In order to grind a work piece 2|, such as that 301 shown in Fig. '1, a grinding wheel I 9 is provided having its peripheral face formed in accordance with the shape of the peripherypof the work piece. It is desirable to provide a truing apparatus to facilitate maintaining the grinding wheel face 35 in. properv condition and in `proper contourto readily applied -to Vor removed from the machine before and after truing. The truing apparatus comprises a base member 30 which is clamped vin adjusted position on the swivel table 20 by 45 means of a manually operable lever clamping mechanism 3l., 'I'his lever operates through Aa toggle lever connection .to rock a clamping arm.

- 32. which engages the lower portion 33 of a dovetailed projection ofthe swivel table 20. An up- 50 per portionv 34 ofthe dovetail is engaged byl'a substantially V- Shaped recess in the base mem- 1 ber 30. i -.An'upper base member 35 is adjustably Supported on thefbase 30 and is arranged to be 55 base member 35 relative to the base 3Q.

`supported to swing about a substantially vertical y A dovetailedslideway d@ is formed on the upper portion of the upper base member 35 which eX- tends longitudinally in a direction substantially parallel to the swivel table. A slide di is provided with a mating dovetailed surface which mates with the dovetail il@ on the base member 355;

A traverseA mechanism is provided for traversing the slide di longitudinally on the dovetailed slideway Qd.- This mechanism may comprise a rotatable screw G2 which is journalled in a bears ing 13 in the upper base member 35. The screw' i2 engages or meshes with a nut t4 which isl xedly supported on and depends from the under side of the slide fil. The outer end of the feed screw ft2 is provided with a manually operable hand wheel i5 by means of which the screw l2 may be readily rotated in either direction to traverse the slide ti longitudinally on its supporting dovetailed slideway 353. p

A pivotally mounted truing tool support d@ is plvotally supported on a pair of opposed pointed screws 5i and 52 which are screw threaded into the bosses 53 and 5t which project from the slide di. The pointed ends of the screws 5l and 52 engage countersunk apertures within the bosses 55 and 56 which are formed'integral with the plvotally mounted supporting member t?.

A follower member 6d is adjustably mounted on the member 5d' and'is arranged to engage a forming bar di which is supported adjacent to the lower portion of they upper base member 3rd..

The forming bar is provided with a surface of a vpredetermined contour to move the truing tool transversely during its traversing movement to produce a predetermined contour on the wheel face. A yieldable means, such as a compression spring 62, is interposed between a horizontally exif tending portion of the member 5@ and the upper surface of the slide di and serves to maintain the follower 60 in operative engagement with the forming bar 6| during the traversing movement of the slide '4L The forming bary 6I is fastened to the lower part of the upper base member 35 within a pairof right angle 4plane surfaces 63 and is held in position thereon by means of screws 6l. l y

A pair of horizontally arranged screws 65 are screw threaded into the upper base member and have their heads engaging notches cut in the upper surface "\of the forming bar 6l. .These screws 65 s Ato aid in adjusting and locating the bar 6l before clamping it in place by means of the screws 64.` i

In order to grind a spherical surface on a work piece, it is 'desirable to produce a grooved. face on' the periphery of the Wheel I9, either concave or convex; which is of. a radius corresponding to the radius of the sphere to be ground. This may be accomplished by providing a, radial truingA device which in the'present case comprises a radial truing supporting bracket 10 which is preferably axis as a pivot. As illustrated in the drawing, the lower end of the pivotal support `5l) is substanatrasos -tially C-shaped and of proper dimensions to receive a substantiallyA C-shaped radial truing bracket lll. A screw li is threaded into the lower arm of the C-shaped projection of the member 50. The screw li has a pointed end l2 which engages a mating aperture in the lower face of the bracket 76. The upper arm 73 of the c-shapecl projection ofthe member 5B is provided with a bearing l@ which is adapted rotatably to support an upper frusto-ccnical bearing surface l on an upwardly extending supporting stud which is either xedly mounted on or formed integral with the. bracket lo. 'I'he axis of the frusto-conicai bearing member 'l5 and the screw li together with its mating aperturel 'l2 are arranged in axial alignment with each other andare arranged in a substantially vertical position. The radial truing bracket 'it serves as a support for a truing'tool l@ `which is adjustably supported on the bracket lil.' The truing tool lL-i is provided with a cylindrical portion which ts within a mating aperture in the radial turing bracket ld. The bracket it is provided with aslot 'Ell (Figs l and 2) which extends through the bracket l@ adjacent to the trulng tool l. A clamping screw lla. passes transversely through the slotted 'portion of the bracket l@ and is threaded into a portion of the bracket and serves to lock the diamond ortruing tool holder 'l5 in adjusted position on the bracket ld.

In order to facilitate operation of the vradial truing device, a shaft 'id extends upwardly from. the bearing surface l5 and is provided at its upper end with an actuating handle i9 by means of which the bracket lil may be rocked about its supporting axis to traverse the diamond or trulng tool l@ in an arcuate path to produce a peripheral groove in the operative face of the grinding wheel of the required radius. By adjusting the diamond or truing tool 16 relatively toward and from the axis of movement of the radial truing bracket ld, the radius of the groove produced by the at` tachment may be readily varied as desired.

Itis desirablethat a locking device be providedl whereby the radial truing bracket l@ may be readily locked to the pivotally mounted support 5@ so that during the traversing movement of the truing tool 'I6 in producing an irregular form on the wheel L9, the truing tool is held in a xed position relative to the pivotally mounted traversable supporting member 50. As illustrated in the drawing, a locking mechanism may comprise a spring pressed plunger 80 having a frusto-,conical end portion which engages a notch or groove 8i cut in the face of the radial truing bracket 10. When the pawl 80 is in .the positiornillustrated in Fig. 1, the bracket 'NI ls'helcl against an oscillat vided on the dovetailed slide 40. 'Ihese s'tops'ilt on the doyetailed slideway I. and are adjustable ing movement. When itis desired to true a radial surfaceor groove in the periphery ofthe wheel,V

longitudinally thereon and serve to limit the longitudinal traversins movement of the slide 4| To facilitate settling the diamond or truing tool 1I so -as to true a groove of'a predetermined radius, a. locating surfacev is .provided on the pivotally mounted supporting frame 50. The locking plunger 8l) is withdrawn and the ,handle 19 turned 180 from the position shown in Fig. 1 so that the radial truing'bracket 10 and the supporting member 5|) are positioned in the manner illustrated in Fig. 6. A gauge block 9| is then inserted in the gap between the locating surface and the truing tool 16, after which the truing tool is adjusted laterally byreleasing the clamping screw 11a and turning an adjusting screw 92 to adjust the position of the truing tool 16 until it contacts with the surface of the gauge block 9l. The-gauge block 9| is' of a predetermined size s0 that when the truing tool is adjusted in accordance with the location of the gauge block, the point of the truing tool 16 projects from the axis of rotation of the radial truing tool holder 10 by 'an amount equal to the radius of the spherical portion .of the work piece to-be ground and equal to the radius of the groove to be generated on the periphery of the grinding wheel I9. After the truthe -stop 86.

ing tool 16 has been adjusted into proper position,

the clamping screw 11a is tightened to lock the truing 'tool in its adjusted position.

The operation of this improved truing -appa-' ratus will bereadily apparent from the foregoing disclosure. The truingtool'16 is first adjusted in the manner above described relative to the radial truing bracket 1I) so that it will true the proper radius on the periphery of the wheel'. The stop 65 on the do'vetailed slide 40 i's then adjustedso that when the truing tool 16 is traversed to its extreme left-hand position (Fig. 2) the stop 85 is adjusted so-that when the slide 4i is traversed into engagement with it, the axis of rotation of the radial truing bracket 10 -will lie in a plane passing through the axis of the groove to be generated uponthe wheel periphery, sothat when the grinding wheel is advanced toward the truing tool and -the truing tool 16 is slowly oscillated by means of the manually operable handle. 19, the truing tool 16 will `traverse in an-arcuate path to produce a periphery of a predetermined groove in the wheel radius. The stop 86 is adjusted longitudinally on the dovetailed slideway so that when the slide l4I is traversed in a direction toward the right.l (Fig. 2) into engagement with the stop 86, the truing tooly 16 will be positioned as indicated in Fig; 5,' slightly beyond the side face of the grinding Wheel I9.

'Ihe truing device'may bev operated in two different manners; first the slide 4lmay be. traversed toward .the right (Fig.- 2) until it engages The radial truing bracket is unlocked by withdrawal of the spring-pressed locking pin 80 and the radial truing-device is rocked sothat the truing tool .16 is in the position 16a (Fig. 3). In this position of the parts, the slide 4I may be traversed toward the left (Fig. 2) to shift the apparatusinto position for truing thegroovein the periphery of the wheel. When the slide 4| of the truing apparatus has been moved into enthe slide 4I may be moved toward the right ,(Fig.

gagement with the stop B5. the handle 19 is rocked or oscillated to pass the truing tool 16 -in an arcuate path across' the wheel periphery. The grind-V ing, wheel may be advanced gradually-during this part of the-truing operation, until the wheel is stoppedby the positive stop on the feeding mechanism, to true the groove to the desired depth. The grinding wheel I9 may thenbe backedoff and the radial truingframe rocked to position the truing tool 16 in the position 16a, after which 2) byrotation of the manually operabletraverse Wheel 45. When the slide '4| engages the'stop 86,

the radial truing bracket 1o is swung intoposition (Fig. 5) and the locking pin- 80 is positioned to lock the bracket 10 tothe pivotally mounted gradually until stopped by the infeed stop and the slide 4| is traversed toward the left (Fig. 2) -by rotation of the traverse wheel 45, during which time the follower 60 follows the shape on the forming bar 6I and the diamond trues a frustoconical surface 96 and rounds the corner 96a between the frusta-conical surface 96 and the groove 95 and then, due to the shape of the forming bar, the diamond or truing tool is moved away from the 4groove of the wheel, thus generating a groove on one portion of the wheel and then producing an adjacent truste-conical surface with a rounded edge portion therebetween,

-If desired, the wheel may be trued by rst truing the' groove to a slight extent, then shifting the radial truing frame 1B and traversing the same to an extreme right-hand position (-Fig. 2), after which the diamond `may be passed to true a. corresponding amount oif the frusta-conicalsurface 95. By utilizing the manually operable feed mechanism together with its positive stop to limitv drawing is'such as to produce a wheel having a circular grooveadjacent to a frusto-conical surface, any desired shape may be' produced by' sub- -fstituting a forming bar 6| having apredetermined shape generated thereon.` 1

It will. thus be seen thatthere has been provided b y this invention apparatus in which the various objects hereinabove set forth together with many thoroughly practical-advantages are successfully achieved. As many `possible embodiments may be made of the above invention andas many changes might be made in the embodiment above set forth, it is to be understood that all fnatter'hereinbefore set forth or shown in the accompanying 'drawing is to be interpreted as illustrative and not in a limiting sense.

I claim-'- f 1. In a grinding wheel truing apparatus, a truing tool, a radial truing device which is pivotally mounted on a substantially vertical axis to support said tool for truing a groove in the operaable support for said device,'a longitudinally traversable support to carry said transversely movable'support and radial truing device, and means including a forming bar and a follower to move said transversely movable support. transversely .rduring its longitudinal movement to true a predetermined form on a grinding wheel.

' 2. In a grinding wheel truing device, a

tool, a piv ota .lly mounted radial Ytruing device to support said vtool for truing a groove in the operative face of a grinding wheel, a pivotally mounted. support for said device, means to lock said device to said support to render said radial truing device operative' or inperative, means to traverse said supportlongitudinally, and means including-a.

forming bar and a follower to rock said support toproduce a predeterminedy form on a grinding Wheel. v t l V3. In a grinding wheeltruing device, a truing tool,;a.pivo tal1y mounted vradial truing device to support said tool, a transversely movable supverse said support longitudinally, and means including a forming bar and a follower to move said A support transversely so as to produce a predetermined form on the operative'i'ace of a grinding wheel.

4. In a grinding wheel truing device, a truing tool, a pivotally mounted radial truing device to support said tool,.a transversely movable support -for said device which supports said radial truingv device with its axis ina substantially vertical position, means to lock said device to said support to render said radiai truing device'either operative .or inoperative, means .including a forming bar and a follower to move said support transversely.

means to locate said lsupport in a predetermined position to locate said radialtruing devicefor truing a groove in a predetermined position on the wheel face, and means to traverse said support to produce a predetermined form on said wheel face adjacent to said groove.

5. A grinding wheel truing apparatus comprising a base, a longitudinally movable'slide thereon; a manually operable nut and screw mechanism to traverse said slide longitudinally relative to said base, a pivotally mounted supporting member on said slide. said pivot being arranged in a substantially horizontal position.a-Iorn1ing bar and a follower one of which is carried by the supporting member and the other by the base, a pivotally mounted radial truing device pivotally supported on said supporting member with its axis in a substantially vertical position, manual means to oscillate said radial truing' device to said slide and arranged to pivot about a substantially horizontal axis, a forming bar and. a

armada follower one of which ls carried by said member Y and the other by the upper base, yieldable means to maintain said follower and bar in operative contact with each other, a pivotally mounted radial truing device pivotally supported on saidl member-.with it axis arrangedsubstantiallyn a vertical position, a truing tool adjustably supported on said device, manual means to oscillate said radial` truing device, meansincluding an adjustable stop. to locate said slide in a predetermined position for truing a groove in the operav itive face of a grinding wheel, and a manually opally mounted on said slide, a forming bar and a follower one of which is carried" by said member and the other by the upper base,yieldable means including a spring acting upon said member to maintain said follower and bar in operative contact with each other, a pivotally mounted radial truing devicey pivotally supported on said memberiwith its pivotal axis in 'a substantially vertical position, a truing tool adjustably supported on said device,.manual means to osciliate said radial truing device'to true a groove in the operative face of a grinding wheel, and a manually operable locking device to render said radial truingdevicepperative or inperative as desired.

.8. In a grinding wheel truing apparatus, an

adiustably mounted truing tool, a pivotally mounted radial truing device to support said truing tool, said radialtruing device being pivotally supported on a' substantially vertical axis, a pivotally mountedsupport i'or said device, means to traverse said support longitudinally,A means including a forming bar and a follower to rock said support to produce a predetermined formed face on a grinding wheel, means to lock said radial truing device to said support during the formed truingA of said wheel, and an adjustable stop to limit the movement of said support in one direction to position the axis of said radial truing device in a predetermined position to true a groove y in the operative face of said grinding wheel adjacent to said formed face;

CARL aimYoAaE. 

